Anaphy For Some Parts Of The Human Brain

Anatomy Brain Skull – made up of 22 bones. Eight bones form the neurocranium (braincase)— including the frontal, parietals, occipital bone, sphenoid, temporals and ethmoid—a protective vault surrounding the brain. Fourteen bones form the splanchnocranium, the bones supporting the face. It also contains the sinus cavities. Meninges - consist of three layers - the dura mater, the arachnoid mater, and the pia mater. Neuron – the four main parts are soma, dendrites, axon and the axon terminal. Soma – central part of the neuron, contains the nucleus of the cell Dendrites – cellular extensions with many branches Axon – fine, cable-like projection which can extend tens, hundreds, or even tens of thousands of times the diameter of the soma in length Axon terminal – contains synapses Cerebrospina fluid - is a clear bodily fluid that occupies the subarachnoid space and the ventricular system around and inside the brain. produced at a rate of 500 ml/day. Internal carotid artery - large arteries are the left and right branches of the common carotid arteries in the neck which enter the skull, as opposed to the external carotid branches which supply the facial tissues. The internal carotid artery branches into the anterior cerebral artery and continues to form the middle cerebral artery Vertebral arteries - These smaller arteries branch from the subclavian arteries which primarily supply the shoulders, lateral chest and arms. Within the cranium the two vertebral arteries fuse into the basilar artery, Circle of Willis - long considered to be an important anatomic vascular formation, provides backup circulation to the brain. Cerebral venous drainage - separated into two subdivisions: superficial and deep. Superficial cerebral venous drainage - superficial system is composed of dural venous sinuses, which have wall composed of dura mater as opposed to a traditional vein. Deep cerebral venous drainage - two transverse sinuses bifurcate and travel laterally and inferiorly in an S-shaped curve that form the sigmoid sinuses which go on to form the two jugular veins. Common carotid artery - it divides in the neck to form the external and internal carotid arteries.

External carotid artery - is a major artery of the head and neck. It arises from the common carotid artery when it bifurcates into the external and internal carotid artery. Anterior cerebral arteries - are a pair of arteries on the brain Middle cerebral artery - arises from the internal carotid and continues into the lateral sulcus where it then branches and projects to many parts of the lateral cerebral cortex White matter – one of the two components of the central nervous system and consists mostly of myelinated axons and is composed largely of lipid tissue veined with capillaries. Grey matter – appears darker due to higher levels of melanin in dopaminergic neurons

Physiology Brain Skull – protector of the brain Neurocranium – protective vault surrounding the brain Splanchnocranium – bones supporting the face Meninges - envelops the central nervous system. The primary function of the meninges is to protect the central nervous system.

Neuron - processes and transmits information by electrochemical signaling. Neurons respond to stimuli, and communicate the presence of stimuli to the central nervous system, which processes that information and sends responses to other parts of the body for action. Soma – most protein synthesis occurs Dendrites - where the majority of input to the neuron occurs Axon - carries nerve signals away from the soma (and also carries some types of information back to it) Axon terminal – specialized structures where neurotransmitter chemicals are released in order to communicate with target neurons. Cerebrospinal fluid - mechanical protection of the brain, distribution of neuroendocrine factors, and prevention of brain ischemia. Common carotid artery - is an artery that supplies the head and neck with oxygenated blood Anterior cerebral arteries - supply oxygen to most medial portions of frontal lobes and superior medial parietal lobes Middle cerebral artery - is one of the three major paired arteries that supplies blood to the cerebrum. Also supplies blood to the anterior temporal lobes and the insular cortices. Basilar artery – supplies blood to the midbrain, cerebellum, and usually branches into the posterior cerebral artery. Circle of Willis – provides interconnections between the internal carotid arteries and basilar artery along the floor of the cerebral vault, providing blood to tissues that would otherwise become ischemic in case one of the supply arteries is occluded. White matter – the tissue through which messages pass between different areas of gray matter within the nervous system. Grey matter – route sensory or motor stimulus to interneurons of the CNS in order to create a response to the stimulus through chemical synapse activity